User`s guide

Operation
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In this mode, only the cold trap is heated and the contents of the trap
are desorbed and vented through the Input Split flow control to
prevent contaminants from entering the GC column.
Trap Test-In this mode, only the cold trap is heated, the contents of
the trap are desorbed onto the GC column and a GC run is started to
verify that the trap is clean before starting a sequence of analyses.
Tube Conditioning-This mode enables a sample tube to be heated
under controlled conditions to remove lower molecular weight
impurities and adsorbed volatiles before it is used for sample
collection. Each tube is leak tested and purged of air prior to
heating.In this mode the cold trap is isolated from the sample tube at
all times.
The tube condition temperature and flow are set using the SET
button on the Options Tab.
Two Stage Desorption and Tube Condition
During Secondary Desorption, the sample is released onto the GC
column and the sample tube is conditioned by heating and venting
through the Input Split flow control to prevent contaminants from
entering the GC column. The analysis time for the GC method will
determine the maximum condition time that can be set for the tube.
The following modes are available with the appropriate optional
accessory installed
Load Internal Standard (ISTD) on Tube - If the instrument has
been equipped with the Internal Standard option, a metered volume
of an analytical standard can be loaded onto a sample tube. This can
be done prior to the sample being collected onto the tube or prior to
the desorption of the collected sample onto the cold trap.
Continuous Online Monitoring - “On-line” is a continuous
sampling mode in which sample is drawn through the ATD/TD and
sampled at regular intervals. During continuous monitoring, the
sample is drawn in through an empty sample tube and onto the cold
trap. The continuous online monitoring accessory is available as an
option. Generally this option is installed at the factory. Contact the
PerkinElmer service department for further information.